Volume 14, Issue 1, 2019/Journal Proceedings in Manufacturing Systems

Abstract: Tools of quality aim to increase the quality in manufacturing systems and hence, maintain or even improve the competitiveness of enterprises. A promising approach to gain the effectiveness of tools of quality is the implementation of these tools in cyber-physical systems. However, there is a gap of knowledge when it comes to such an implementation – in particular concerning the relevant data of the tools of quality. In order to deal with this issue, this paper presents results from an examination of seven tools of quality regarding their relevant data when it comes to an implementation in a cyber-physical system. Firstly, different key characteristic of cyber-physical systems are carved out, which have to be considered. Then, seven basic tools of quality are examined in detail in order to identify their specific relevant data. The identified data are sorted into the categories basic data, input data and output data. Subsequently, an approach for a systematic identification of data flows between the tools of quality based on a pairwise evaluation is described. Moreover, major data flows between tools of quality are proposed. Finally, findings of a practical implementation of tools of quality in a cyber-physical system are presented. It has been proven that a real-time capability as well as a location-independence can be achieved when tools of quality are implemented in cyber-physical systems under consideration of the data identified in this paper.

Key words: Cyber-physical systems, production optimization, quality management, data examination, quality improvement, manufacturing systems.

pp. 49-54 View full text

Graphical & analytical modeling of the cutting scheme used to generate square holes with slotting tools having periodic profile

Mihail BORDEANU¹, Gabriel FRUMUŞANU^2,*, Nicolae OANCEA³

¹⁾ PhD Student, Manufacturing Engineering Department, "Dunărea de Jos" University of Galaţi, Romania

^{2), 3)} Prof., PhD, Manufacturing Engineering Department, "Dunărea de Jos" University of Galaţi, Romania

Abstract: The machining of interior surfaces having non-involute profile, by rolling method, with slotting tools generating by enwrapping, leads to an important variation of the detached chips area. This further leads to the uneven loading of tool cutting edges, from energetic point of view, with negative consequences in what concerns the tool wear or the elastic deformation of both tool and machined part, which, at its turn, causes machining errors. At the same time, the uneven loading of the machine tool mobile parts worsen the manufacturing system functionality. This paper addresses the case of generating square holes with slotting tools having periodic profile. It presents an analytical method for tool profiling and the graphical modeling in CATIA of the cutting scheme, when machining with constant circular feed. On this base, the machining process smoothening can be obtained by subsequently adopting a variable circular feed of the rolling motion, such as the detached chips have constant area in frontal section. A numerical application concerning an actual case is also included.

Key words: square hole machining, slotting tools with periodic profile, graphical modeling, constant area of detached chips, circular feed variation law.

pp. 55-60 View full text

New method for sending data to the cloud from an OPC UA client application

Gicu-Călin DEAC^1,*, Crina Narcisa GEORGESCU², Cicerone Laurențiu POPA³,

Costel Emil COTEȚ⁴, Florina CHISCOP⁵

¹⁾ PhD Student, Robots and Manufacturing Systems Department, University "Politehnica" of Bucharest, Romania

³⁾ Associate Prof., PhD, Robots and Manufacturing Systems Department, University "Politehnica" of Bucharest, Romania

⁴⁾ Prof., PhD, Robots and Manufacturing Systems Department, University "Politehnica" of Bucharest, Romania

⁵⁾ Lecturer, Ph.D., Robots and Manufacturing Systems Department, University "Politehnica" of Bucharest, Romania

Abstract: The present paper presents a new method for sending data to the cloud from a Client OPC UA Application (Open Platform Communications Unified Architecture), using PNG images as a medium. The data values encoded as pixel colors of images, using different encoding methods for each data type (text, integer, float, Boolean) are also encrypted using an image as a symmetric encryption key and are stored in the cloud in a time base folder structure. This method of sending and storing the data using an encrypted image format assure a better data compression, security and speed, compared with the actual JSON format which is text based and open. Based on the stored image files can be generated some index image files containing the data values of each property (sensor value) for a chunk of time, in this way reducing the total number of images and increase the compression of data, because of the small allocation space on disk and similarity of data that are better compressed by the LZW compression algorithm of PNG image format. This indexed image file can replace the actual SQL or NoSQL databases and can be read by multithreaded agents using multicore processors for faster interrogation and easily replicated to other servers by copying the new generated files.

Key words: IIoT, OPC UA, Big Data, Cloud, Data encryption.

pp. 61-66 View full text

Error of the threaded surface minor diameter due to the position of the threading tool nose

Adriana MUNTEANU¹, Laurenţiu SLĂTINEANU², Ionel COMAN³, Gheorghe NAGÎŢ^4,*,

Adelina HRIŢUC⁵, Ana Maria BOCĂNEŢ⁶, and Irina BEŞLIU BĂNCESCU⁷

¹⁾Assoc. Prof., PhD, Department of Machine Tools and Tools, “Gheorghe Asachi” Technical University of Iaşi, Romania

²⁾Prof., PhD, Department of Machine Manufacturing Technology, “Gheorghe Asachi” Technical University of Iaşi, Romania

³⁾PhD Student, Department of Machine Manufacturing Technology, “Gheorghe Asachi” Technical University of Iaşi, Romania

⁴⁾Prof., PhD, Department of Machine Manufacturing Technology, “Gheorghe Asachi” Technical University of Iaşi, Romania

⁵⁾Master Student, Department of Machine Manufacturing Technology, “Gheorghe Asachi” Technical University of Iaşi, Romania

⁶⁾Lecturer, PhD, Department of Machine Tools and Tools, “Gheorghe Asachi” Technical University of Iaşi, Romania

⁷⁾Lecturer, PhD, “Ştefan cel Mare”, Department of Mechanics and Technology, University of Suceava, Romania

Abstract: The threads are surfaces commonly used when demountable joints are necessary. Some of the threading methods involve the use of threading tools on a lathe. The accuracy of the threaded surfaces depends on the positioning of the threading tool relative to the workpiece axial plane. In order to evaluate the influence of the positioning the threading tool nose on some accuracy parameters of the threaded surfaces, a theoretical model was established on the base of geometric considerations. The model highlights the influence of the distance between the threading tool nose and the workpiece axial plane on the value of the threaded surface minor diameter. Since the model does not offer a direct image concerning the intensity of the influence exerted by the threading tool nose position on the value of the threaded surface minor diameter, a power type model was also established considering the initial geometric model. To experimentally investigate the influence exerted by distinct rotations and displacement of the threading tool around and along the axes of a Cartesian coordinate system, a device for controlled changing of the position of the threading tool was designed and achieved. The preliminary experimental research proved the possibilities of using such a device to investigate the influence exerted by the positioning of the threading tool on the parameters specific to a threaded surface.

Key words: threaded surfaces, accuracy, threading tool position, geometric model, power type model, experimental device.

pp. 67-72 View full text

Video working instruction system

Crina Narcisa GEORGESCU¹, Gicu-Călin DEAC ², Florina CHISCOP³,

Cicerone Laurențiu POPA^4,*, Costel Emil COTEȚ⁵

¹⁾ Ph.D. Student, Robots and Production Systems Department, University "Politehnica" of Bucharest, Romania

²⁾ Ph.D. Student, Robots and Production Systems Department, University "Politehnica" of Bucharest, Romania

³⁾ Lecturer, Ph.D., Robots and Production Systems Department, University "Politehnica" of Bucharest, Romania

⁴⁾ Associate Prof., Ph.D., Robots and Production Systems Department, University "Politehnica" of Bucharest, Romania

⁵⁾ Prof. Ph.D., Robots and Production Systems Department, University "Politehnica" of Bucharest, Romania

Abstract: The present paper presents a new working instruction system placed on the assembly line, composed by few synchronized video displays for providing interactive procedural instructions and a QR (Quick Response) code web-based application for gathering additional information and publishing comments, requests, and evaluation. This system helps operators memorize and perform operations correctly, respecting the recommended time at each workstation, ultimately increasing productivity and reducing scrapping on the assembly line. Two questionnaire based surveys were conducted in order to evaluate the proposed video working instruction system and to evaluate the work carried out within the workstations. Results indicate that the proposed system is more efficient, increases productivity, produces a lower level of waste and is accessible to users.

Keywords: Working Instructions, QR code, signage, assembly line, digitalization.

pp. 73-80 View full text

AS/RS automated storage system with mixed palletizing – offline simulation

Ancuța SIMION^1,*, Adrian Florin NICOLESCU², Cristina PUPĂZĂ³

¹⁾ PhD Student, Numerical Simulation Specialist, NVH Dept., Renault Technologie Roumanie, Bucharest, Romania

²⁾ ³⁾Prof. PhD, Robots and Manufacturing Systems Dept., University "Politehnica" of Bucharest, Romania

Abstract: The study is realized during the bachelor project developed for robotics specialization and presents the mixed palletizing operation into the automated storage system, called AS/RS. The paper is based on the research through which the industrial robots integrated in the system and process are analyzed, end-effectors which can be used, possibility to load-unload the highest storage, types of objects that can be palletized or how the order will be on pallets. The most important step was to see what other companies developed and how they integrated the entire systems in the process. That involved a lot of work and research to find patents, scientific articles, animation and how the automated storage system can be improved. It was studied the patent developed by the Bastian Company, which had an automated storage system with mixed palletizing. In the patent it could not be found the loading-unloading system, shuttle system, and pallets supplier. Almost all systems were shaped and designed in NX-CAD software, except conveyors, industrial robots and translation module produced by ABB Company. After that, all components were loaded in the Process Simulate – dedicated software for achieving offline simulation.

Key words: industrial robot, mixed palletizing, storage system, offline simulation, Process Simulate.

Electronic mail: orgcom@icmas.eu